You guys are usually pretty useless in this forum but i am willing to give it a shot.

Last night i tore down my iPhone 4 because the sleep button was getting extremely hard to press to the point where it didnt work anymore. so i had the phone in peices and yes fyi i have done this before, torn apart 3G's 3gs's 4's and a few 4s's so i have done this before. So anyways put it all back together after cleaning the sleep button, turned it on by plugging it in. the phone powered up and everything touch screen worked lcd worked but power button didnt so i had no way of turning off i simply unplugged the battery and fiddled with the power button put it back together and now all my features work i can use voice dial and call people but my screen is on but its just black.